I attended Dell Technology World recently and on the show floor was a container that looked like it would be more at home on a “Star Trek” set than in a data center.
It was a server immersion chamber from Green Revolution Cooling (GRC) that’s used to reduce server energy costs while increasing reliability.
I’ve been following liquid cooling in data centers and in PCs for several decades now, and it has several advantages over air cooling. Apparently, Dell and Intel are working closely with GRC to create a new generation of immersed servers that will outperform their air-cooled equivalent servers and at a lower cost.
Let’s look at immersion cooling this week:
Immersion cooling technology
After expressing interest in the technology, GRC’s CEO, Peter Poulin, agreed to chat with me about the progress GRC has made, how the technology is changing a growing number of data centers, and particularly why Dell and Intel are redesigning servers for the process.
Immersion cooling submerges the server in a non-conductive, non-corrosive liquid that is then usually pumped out and back into the building after going through an external heat exchanger. The coolant is a human-safe synthetic hydrocarbon liquid with decent thermal transfer properties that is generally pumped in under the servers and then extracted from the top to be cooled.
The liquid isolates the servers from the air, and the process doesn’t require fans inside the data center, so it remains quiet. You don’t have to worry about corrosion, so you don’t need to aggressively remove water from the air. You don’t really need a specially cooled room for the data center, as all the cooling takes place within the GRC immersion unit.
All the fans are removed, and either the motherboard is tricked into thinking it is connected to a fan, so the server will boot, or firmware is changed, so the server no longer looks for the fans anymore. A pump then circulates the liquid in and out of the servers and building to accomplish the cooling.
Although spills are rare, each system contains a repository to catch any leaks and sensors to report a leak should one occur. These sensors also remind you about preventive maintenance, which largely consists of replacing the filters on a six-month rotation to assure the cooling liquid doesn’t become contaminated.
Board replacement isn’t adversely impacted, the tech doesn’t need to wear gloves, as the liquid is non-conductive, and they only need something to wipe the coolant off their hands and anything they remove from the server.
Use cases and benefits
The solution has been deployed in 21 countries and has been particularly popular for crypto mining, which uses lots of ASYCs, making the related servers more difficult to adequately cool, and for mini-data centers at the edge where environmental conditions would typically be too harsh for most servers.
Poulin said that the core benefits of the implementations were a reduction in power used during peak loads, the near elimination of data center fan noise, and the elimination of server environmental failure caused by corrosion.
Users are reporting significant CapEx savings for a new data center using immersion as well as OpEx savings for immersion servers, according to Poulin.
Server redesign and warranty
Dell has embraced this approach and will warranty servers approved for immersion.
But both Intel and Dell realized that cooling mechanisms designed for air aren’t going to work well with a liquid, so they are working together with GRC to create server variants that are specifically designed for immersion.
The benefits should significantly exceed the servers that were simply immersed with only the removal of their fans.
The server future is immersion
The benefits of immersion are significant, ranging from CapEx and OpEx savings to making the data center a far less noisy place to work as well as higher reliability and reduced loading on a building’s HVAC system, which can become important during the summer months.
In some implementations, you don’t even need a data center. You just use the containment unit alone to cool and protect the related servers, making this solution ideal for remote servers located in hostile environments.
In the end, I think immersion is the future of servers. The benefits are too compelling, and it appears GRC, Dell, and Intel are already positioning to benefit from that future.